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101.
Meng X  Song Y  Hou H  Han H  Xiao B  Fan Y  Zhu Y 《Inorganic chemistry》2004,43(11):3528-3536
Four novel cadmium-btx (btx = 1,4-bis(triazol-1-ylmethyl)benzene) coordination polymers [Cd(btx)(2)(NO(3))(2)](n)(1), [Cd(btx)(2)Cl(2)](n)(2), [Cd(btx)(SO(4))(H(2)O)(2)](n)(3), and [Cd(btx)(S(2)O(7))(H(2)O)](n)(4) have been prepared by hydrothermal reaction (140 or 180 degrees C) and characterized. Both 1 and 2 have two-dimensional rhombohedral grid structures, 3 possesses a two-dimensional rectangular grid structure, and 4 displays a three-dimensional framework, which is formed by btx bridging parallel layers. To the author's best knowledge, polymer 4 is the first Cd(II) polymer in which the Cd(II) ion is eight-coordinated in a hexagonal bipyrimidal geometry. In addition, we studied the effects of temperature on the hydrothermal reaction system of btx and CdSO(4) and found that different products can be obtained at different temperatures. Furthermore, polymer 3 possesses a very strong third-order NLO absorptive effect with an alpha(2) value of 1.15 x 10(-)(9) m W(-1). Polymers 2-4 display strong fluorescent emissions in the solid state at room temperature. The DTA and TGA results of the four polymers are in agreement with the crystal structures.  相似文献   
102.
Hou H  Li G  Li L  Zhu Y  Meng X  Fan Y 《Inorganic chemistry》2003,42(2):428-435
Three novel ferrocenecarboxylato-bridged lanthanide dimers [Gd2(mu 2-OOCFc)2(OOCFc)4(MeOH)2(H2O)2].2MeOH.2H2O (1) (Fc = (eta 5-C5H5)Fe(eta 5-C5H4)), [Nd2(mu 2-OOCFc)2(OOCFc)4(H2O)4].2MeOH.H2O (2), and [Y2(mu 2-OOCFc)2-(OOCFc)4(H2O)4].2MeOH (3) have been synthesized and characterized by single-crystal X-ray crystallography. In each complex, two Ln(III) (Ln = Gd, Nd, or Y) ions are bridged by two ferrocenecarboxylate anions as asymmetrically bridging ligands, leading to dimeric cores, [Ln2(mu 2-OOCFc)2]; each Ln(III) ion has an irregular polyhedral coordination environment with nine coordinated oxygen atoms derived from the ferrocenecarboxylate ligands and coordinated solvent molecules. In the solid-state structure of compound 1, [Gd2(mu 2-OOCFc)2(OOCFc)4(MeOH)2(H2O)2] groups are joined together by hydrogen bonds forming a two-dimensional network. Both compounds 2 and 3 show one-dimensional chain structures by hydrogen bonding; they are different from 1. Magnetic measurements show unexpected ferromagnetic coupling between the gadolinium(III) ions; the best fittings to the experimental magnetic susceptibilities gave J = 0.006 cm-1 and g = 2.0 for 1. The magnetic behavior for 2 was also studied in the temperature range of 1.8-300 K.  相似文献   
103.
Hou H  Li L  Zhu Y  Fan Y  Qiao Y 《Inorganic chemistry》2004,43(15):4767-4774
Treatment of p-ferrocenylbenzoate [p-HOOCH4C6Fc, Fc = (eta5-C5H5)Fe(eta5-C5H5)] with Mn(OAc)2 x 2H2O or Cd(OAc)2 x 2H2O afforded one-dimensional linear chain polymer [[Mn(OOCH4C6Fc)2(mu2-OH2)(H2O)2](H2O)]n (1), double-bridge polymer [Mn(mu2-OOCH4C6Fc)2(phen)]n (phen = phenanthroline) (2), and ladderlike framework [[Cd(mu2-OOCH4C6Fc)(eta2-OOCH4C6Fc)(bbp)](CH3OH)]n (bbp = 4,4'-trimethylene-dipyridine) (3). The solution-state cyclic voltammograms indicate that the half-wave potentials of the ferrocenyl moieties in these polymers are all shifted to positive potential compared to that of sodium p-ferrocenylbenzoate. Both 1 and 2 behave as 1D Heisenberg Mn(II) chains with weak intrachain antiferromagnetic interactions between the local high-spin Mn(II) ions, and the exchange coupling parameters J (-5.20 and -3.25 cm(-1) for 1 and 2, respectively) are larger than those of most of the reported di-Mn(II) complexes that contain mu2-aqua and mu2-carboxylato units and one-dimensional Mn(II) carboxylic polymers.  相似文献   
104.
培养了苦味酸锂与二苯并18-冠-6缔合物的单晶体[Li(pic)(H_2O)]_2·[C_(20)H_(24)O_6],化学式为C_(32)H_(32)Li_2N_6O_(22),用X射线法测定了缔合物的晶体结构,证明该晶体属单斜晶系,空间群为P2_1/m,晶胞参数:a=8.299(2),b=25.216(3),c=9.158(2)(?),β=100.34(2)°,V=1885.4(?)~3,Z=2。  相似文献   
105.
针对IgA肾病研究制备用于IgA吸附的免疫吸附剂.采用不同活化方法、不同配基制备吸附剂,测定吸附效率并进行比较.体外吸附实验表明吸附剂对IgA肾病病人血清中的IgA具有较强的吸附性能;对正常人血液进行血液相容性实验及对健康小鼠的急性毒性实验证明该吸附剂具有良好的血液相容性且安全、无毒.该吸附剂可作为IgA肾病的免疫吸附剂.  相似文献   
106.
1. INTRODUCTION The development of cell based organs and tissue-engineering devices such as hybrid artificial liver requires a large number of cells be cultured for the replacement of damaged tissue [1,2]. Since its introduction in 1967, microcarriers culture has been applied successfully in growing primary cells and cell lines with the advantage of attaining high cell density [3,4]. Spheroid culture is another promising hepatocytes culture method to enhance the cell density and metaboli…  相似文献   
107.
Meng X  Song Y  Hou H  Fan Y  Li G  Zhu Y 《Inorganic chemistry》2003,42(4):1306-1315
Three novel coordination polymers [Pb(bbbm)(2)(NO(3))(2)](n) (bbbm = 1,1'-(1,4-butanediyl)bis-1H-benzimidazole) 1, [Zn(bbbt)(NCS)(2)](n) (bbbt = 1,1'-(1,4-butanediyl)bis-1H-benzotriazole) 2, and [Zn(pbbt)(NCS)(2)](n) (pbbt = 1,1'-(1,3-propylene)bis-1H-benzotriazole) 3 were synthesized and structurally characterized. Polymer 1 exhibits a two-dimensional rhombohedral grid network structure, the dimensions of the grid are 14.274 x 14.274 A, and the diagonal-to-diagonal distances are 24.809 x 14.125 A. Polymer 2 possesses a concavo-convex chain structure different from those of the known one-dimensional polymers, which are linear chain, zigzag chain, helical chain, double-stranded chain, and ladder chain. Polymer 3 exhibits a one-dimensional zigzag chain structure, and these chains were packed as an.ABAB. layered structure. The third-order nonlinear optical (NLO) properties of polymers1, 2, and 3 were determined with a 7-ns pulsed laser at 532 nm. 1 shows strong third-order NLO absorptive and refractive properties, and its alpha(2) and n(2) values were calculated to be 5.8 x 10(-)(9) m W(-)(1) and 4.67 x 10(-)(18) m(2) W(-)(1) in a 3.4 x 10(-)(4) mol dm(-)(3) DMF solution, respectively. Both 2 and 3 exhibit weaker NLO absorption and strong refractive properties, and their n(2) values are 4.53 x 10(-)(18) m(2) W(-)(1) for 2 in a 5.2 x 10(-)(4) mol dm(-)(3) DMF solution and 3.02 x 10(-)(18) m(2) W(-)(1) for 3 in a 4.35 x 10(-)(4) mol dm(-)(3) DMF solution. The chi((3)) values of 1, 2, and 3 were calculated to be 1.67 x 10(-)(11), 1.62 x 10(-)(11), and 1.08 x 10(-)(11) esu, respectively, and the values are larger than those of the reported coordination polymers. We deduce that the valence shell structures of metal ions may have some influence on the strength of NLO properties, and discuss the relationships between the crystal structures of coordination polymers and the observed NLO properties.  相似文献   
108.
郑会勤  樊耀亭 《分子催化》2023,37(4):331-341
合成并表征了两个新的具有 “开放型蝶形” 结构的[2Fe2S]化合物AB; 并以AB为催化剂、 藻红B钠盐 (EBS2-) 为光敏剂、 三乙胺 (TEA) 为电子给体和质子源, 构建了一个均相光催化产氢体系. 结果表明: 体系在pH为12, 体积比为1∶1的CH3CN/H2O溶液中,产氢活性最高,经4 h可见光照射,最大产氢量分别为156.1 μmol (37.9 TON vs. A) 和18.4 μmol (TON 4.6 vs. B); 催化剂中含有质子捕获位点, 有利于形成产氢活性中间体H2-Fe2S2(η2-H2-FeIIFeI) 物种, 从而提高催化剂的产氢活性. 在当前的体系中, 还原态的 FeIFe0 物种通过1* EBS2-转移到FeIFeI中心上, 然后再经历一个EECC (化合物A)ECEC (化合物B), 形成产氢活性中间体H2-Fe2S2(η2-H2-FeIIFeI)物种, 最终产生H2分子, 并使FeIFeI 物种再生.  相似文献   
109.
In this paper, fractal theory is successfully applied to the analysis of fractal properties of Mandarin speech. First, a new algorithm of the arithmetical progression scales gridding dimension, based on the conventional Box Dimension, is presented to reduce the computational cost. Second, the distribution laws of fractal dimension of Mandarin speech have been obtained by calculating and statistically analyzing the arithmetical progression scales gridding dimension of 21 consonants and 38 vowels of Mandarin speech. The preliminary results in our experiment show that Mandarin speech has the scale-invariant property and that the arithmetical progression scales gridding dimension can indicate the complexity and irregularity degree of the waveform of Mandarin speech signals. The novel discoveries in our studies imply that fractal theory has a good potential in the field of speech signals processing.  相似文献   
110.
聚乙烯醇包埋龟裂链霉菌对水中Pb~(2 )吸附性能的研究   总被引:4,自引:0,他引:4  
本文研究了聚乙烯醇包埋龟裂链霉菌菌丝体的包埋条件及包埋后对水中Pb2 的吸附作用。结果表明,包埋比例为3/1(W/W),聚乙烯醇浓度为10%,海藻酸钠浓度0.2%,在含2?Cl2饱和硼酸溶液中固化24h是包埋反应的最佳条件。包埋后的饱和吸附量可达73.0mg/g,比未包埋龟裂链霉菌下降 47.1% 。pH值对吸附量的影响较包埋前下降。升高温度有利于吸附。  相似文献   
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